ATV buffering this movie, Is bitrate too high?
#1
All,

This file is struggling to play on the AppleTV1. I receive consistent buffering. I read that XBMC buffers at 2x the bitrate. I have verified my ATV can and network can comfortably do up to 80 mbps. The image below shows the peaks and valleys of the file.

The max bitrate is 44128kbps. The average bitrate is 31198kbps.

Why is this buffering?

Image
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#2
Do you have a Broadcom Crystal HD (wiki) card installed on the Apple TV 1?
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#3
Yes. I have the 15 version. the drivers are installed and the box is checked within XBMC
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#4
I should also mention that the movie played perfectly when it was locally stored.
i.e. stored on the appletv.
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#5
I can also post additional media info if necessary. However, I think all that is needed is listed above
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#6
You need media info that graph says nothing useful on how the file has been encoded
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#7
Ok, Here it is....

Like I said, it played fien when I copied it onto the ATV1.

Code:
General
ID                                       : 0 (0x0)
Complete name                            : E:\Videos1\Movies\Indiana Jones and the Kingdom of the Crystal Skull (2008)\Indiana Jones and the Kingdom of the Crystal Skull (2008).m2ts
Format                                   : BDAV
Format/Info                              : Blu-ray Video
File size                                : 34.1 GiB
Duration                                 : 2h 2mn
Overall bit rate mode                    : Variable
Overall bit rate                         : 39.9 Mbps
Maximum Overall bit rate                 : 48.0 Mbps

Video
ID                                       : 4113 (0x1011)
Menu ID                                  : 1 (0x1)
Format                                   : AVC
Format/Info                              : Advanced Video Codec
Format profile                           : [email protected]
Format settings, CABAC                   : Yes
Format settings, ReFrames                : 4 frames
Codec ID                                 : 27
Duration                                 : 2h 2mn
Bit rate mode                            : Variable
Maximum bit rate                         : 37.0 Mbps
Width                                    : 1 920 pixels
Height                                   : 1 080 pixels
Display aspect ratio                     : 16:9
Frame rate                               : 23.976 fps
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Progressive
Color primaries                          : BT.709-5, BT.1361, IEC 61966-2-4, SMPTE RP177
Transfer characteristics                 : BT.709-5, BT.1361
Matrix coefficients                      : BT.709-5, BT.1361, IEC 61966-2-4 709, SMPTE RP177

Audio #1
ID                                       : 4352 (0x1100)
Menu ID                                  : 1 (0x1)
Format                                   : AC-3
Format/Info                              : Audio Coding 3
Format profile                           : TrueHD / Core
Mode extension                           : CM (complete main)
Muxing mode                              : Stream extension
Codec ID                                 : 131
Duration                                 : 2h 2mn
Bit rate mode                            : Variable / Constant
Bit rate                                 : Unknown / 640 Kbps
Maximum bit rate                         : 5 022 Kbps / 640 Kbps
Channel(s)                               : 6 channels
Channel positions                        : Front: L C R, Side: L R, LFE
Sampling rate                            : 48.0 KHz
Bit depth                                : 16 bits
Compression mode                         : Lossless / Lossy

Audio #2
ID                                       : 4353 (0x1101)
Menu ID                                  : 1 (0x1)
Format                                   : AC-3
Format/Info                              : Audio Coding 3
Mode extension                           : CM (complete main)
Codec ID                                 : 129
Duration                                 : 2h 2mn
Bit rate mode                            : Constant
Bit rate                                 : 640 Kbps
Channel(s)                               : 6 channels
Channel positions                        : Front: L C R, Side: L R, LFE
Sampling rate                            : 48.0 KHz
Bit depth                                : 16 bits
Compression mode                         : Lossy
Stream size                              : 561 MiB (2%)

Audio #3
ID                                       : 4354 (0x1102)
Menu ID                                  : 1 (0x1)
Format                                   : AC-3
Format/Info                              : Audio Coding 3
Mode extension                           : CM (complete main)
Codec ID                                 : 129
Duration                                 : 2h 2mn
Bit rate mode                            : Constant
Bit rate                                 : 640 Kbps
Channel(s)                               : 6 channels
Channel positions                        : Front: L C R, Side: L R, LFE
Sampling rate                            : 48.0 KHz
Bit depth                                : 16 bits
Compression mode                         : Lossy
Stream size                              : 561 MiB (2%)


[/code]

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#8
What protocol are you using to share the files over the network? SMB? AFP? NFS? It's possible there's some weird overhead that pops in and out that will cause occasional buffering.
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#9
When you say that this plays perfectly locally what do you exactly mean?
Have you let this movie play for say half hour and checked that it does not drop frames?
And what is the file server and how do you connect to it?
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#10

I have tried SMB, NFS and FTP. In order of best to worst it has been FTP -> SMB -> NFS. All being served up from a Windows Home Server 2011.

FTP is the closest, but I see that little streaming pop up message in bottom corner of screen saying "cache filled before reaching required amount..."

Clicking "o" on keyboard I can see aq and vq struggling to stay above 0. I see that MBit/s range from 28-38 Mb but the machine is capable of 80Mb and I have seen it pull there.

some interesting things from log are...

Code:
CDVDInputStreamFile::SetReadRate - set cache throttle rate to 5113603 bytes per second
Code:
DEBUG: CDVDPlayerAudio:: Discontinuity - was:1624238138.422667, should be:1624233699.666667, error:-4438.756000
Code:
WARNING: CCoreAudioPerformance: Outgoing bitrate is lagging. Target: 576000, Actual: 569441. deltaTime was 1010
Code:
WARNING: CDVDMessageQueue(video)::Get - asked for new data packet, with nothing available



(2012-03-16, 05:51)Ned Scott Wrote: What protocol are you using to share the files over the network? SMB? AFP? NFS? It's possible there's some weird overhead that pops in and out that will cause occasional buffering.

I mean, copied onto the device, I have 0 stuttering, 0 buffering, 0 dropped frames.

Yes, I have let it play for the entire movie and it did not drop frames when played off of the atv not the network.

connected to windows home server 2011. sharing options are ftp, smb and nfs. in order of success its ftp -> nfs -> smb.

(2012-03-16, 09:49)interceptor121 Wrote: When you say that this plays perfectly locally what do you exactly mean?
Have you let this movie play for say half hour and checked that it does not drop frames?
And what is the file server and how do you connect to it?

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#11
The log is too big to fit on pastebin so I posted it to skydrive.

XBMC.log

The first 10,100+ lines are a result of playing over the network. Lines ~10200 - 10400 are playing the file from the machine.

What's weird is all the references to the iron man 2 bluray. I have no idea why its trying to open that.

Before you ask, I am using ftp://127.0.0.1 so that I can use mysql. I do file substitution on the apple tv to redirect to 192.168.1.120. I have also trying accessing the ftp server directly without the file substitution, no difference.
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#12
anyone have any thoughts on this?

does anyone think this could be a bug associated with TrueHD or DTS-HD decoding.
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ATV buffering this movie, Is bitrate too high?0